How to detect an earthquake in 16 seconds?

In July 2020, PublicSonar detected an earthquake within 16 seconds after it occurred. Twitter data included citizen reports as well as location and sentiment. Below you can read more on how social media data is used to monitor an earthquake.

The area of Groningen is most seismically active in the Netherlands. Earthquakes, triggered by gas extraction, cause not only damage but also social unrest. A lot of stakeholders need the earliest information after an earthquake occurs. Local authorities and emergency responders have set up PublicSonar to monitor the region for earthquake detection. By doing so, they ensure to never miss citizen signals for earthquakes and get the quickest alert.

Earthquake detection within 16 seconds with context, location & sentiment

On July 14th, 2020 an earthquake occurred at 17:18:47 PM. PublicSonar detected the first 6 Tweets within 16 seconds. They included citizen reports of the earthquake as well as location and sentiment. A minute later, PublicSonar recognised 10 new messages of citizens signalling the earthquake. Only two minutes after the earthquake, an automated PublicSonar alert was triggered at 17:21. It notified authorities and emergency responders by phone and email about the earthquake.

The PublicSonar alert was accurate, real time and gave complete situational awareness. Thus, a time advantage to crisis managers and emergency responders. In comparison, public news services reported 29 minutes later. While a popular online Dutch news outlet was 69 minutes after the alert.

This case study shows the power of open data combined with technological innovation. PublicSonar gives organisations managing crises the information they need to respond timely.

Open data: essential for managing crises

Did you know that every second there are 6000 new Tweets, adding up to 500 million per day? Messages are shared online at an unprecedented rate. Internet users express their thoughts and opinions, share sentiment and information online.

The number of people posting about crises and events has enormously increased. Information shared by citizens online is valuable for crisis managers and first responders. This value is threefold. For ‘early warning’, situational awareness and improving operational response to the crisis.

How to utilise crowdsourced information for emergency response and crisis management?

The number of messages online skyrocket during crises, public disruptions and events. This results in an enormous information overload. Hence, manually filtering messages to base a conclusion – or let alone the next action on – is impossible. The overload of information also brings the risk of missing valuable information.

Utilising crowdsourced information for crisis management and emergency response requires automated filters to extract relevant messages. PublicSonar is unique in doing precisely that. Our smart algorithms collect data, filter information and detect sentiment. The technology can identify when an incident occurs to send an automated alert to emergency responders. Curious how PublicSonar can help you with emergency planning and response? Contact us at, reach out through our contact page or follow us at LinkedIn.

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